Overview
Definition:
Anastomotic bleed after colorectal surgery refers to bleeding originating from the site where two segments of the colon or rectum have been surgically joined
This can range from minor oozing to significant hemorrhage requiring intervention
It is a critical postoperative complication impacting patient recovery and outcomes.
Epidemiology:
The incidence of anastomotic bleeding after colorectal surgery varies significantly in literature, typically reported between 1% and 10%
Factors influencing this include the type of anastomosis, surgical technique, patient comorbidities, and anticoagulant use
Early bleeding (within 48 hours) is more common than delayed bleeding.
Clinical Significance:
Anastomotic bleed is a serious complication that can lead to hemodynamic instability, requiring blood transfusions, prolonged hospitalization, and potentially reoperation
It can compromise the integrity of the anastomosis, increase the risk of anastomotic leak, and significantly affect patient morbidity and mortality
Prompt and accurate diagnosis and management are paramount.
Clinical Presentation
Symptoms:
Hematochezia (bright red or dark blood per rectum)
Melena (if bleeding is brisk and proximal)
Abdominal pain or discomfort
Dizziness or syncope
Signs of hypovolemic shock: tachycardia, hypotension, pallor, cool clammy skin
Decreased urine output.
Signs:
Vital sign derangements: tachycardia, hypotension
Abdominal distension or tenderness
Palpable mass in the abdomen if a hematoma forms
Signs of hypovolemic shock
Per rectal examination may reveal blood or clots.
Diagnostic Criteria:
No formal strict diagnostic criteria exist
Diagnosis is primarily clinical, based on the presence of significant rectal bleeding post-colorectal surgery, in conjunction with exclusion of other sources of bleeding and supported by imaging or endoscopic findings
Hemodynamic instability in the early postoperative period is a strong indicator.
Diagnostic Approach
History Taking:
Detailed history of the surgical procedure, including type of anastomosis, any intraoperative difficulties, and use of drains
Time of onset of bleeding relative to surgery
Amount and character of bleeding
History of anticoagulant or antiplatelet use
Coagulopathy history
Comorbidities.
Physical Examination:
Assess for hemodynamic stability: vital signs, signs of shock
Perform a thorough abdominal examination for tenderness, distension, or masses
Digital rectal examination to assess for gross blood, clots, or local lesions
Assess for signs of anemia.
Investigations:
Complete Blood Count (CBC) to assess hemoglobin and hematocrit levels, and platelet count
Coagulation profile (PT, INR, aPTT) to rule out coagulopathy
Type and crossmatch for blood products
Imaging: CT angiography may be useful to identify active extravasation or pseudoaneurysms
Flexible sigmoidoscopy or colonoscopy to visualize the anastomosis and identify the bleeding source.
Differential Diagnosis:
Other causes of postoperative rectal bleeding: staple line bleeding, suture line dehiscence with distal bleeding, diverticular bleeding, ischemic colitis, hemorrhoidal bleeding, anal fissures, postoperative pancreatitis complications, arteriovenous malformations
Bleeding from other surgical sites if generalized coagulopathy is present.
Management
Initial Management:
Hemodynamic resuscitation: intravenous fluids, blood transfusion as needed
Correction of coagulopathy with fresh frozen plasma (FFP), vitamin K, or platelet transfusion
Nasogastric tube insertion to assess for upper GI bleed (less common but possible)
Stop anticoagulants if clinically appropriate, consult hematology.
Endoscopic Management:
Flexible sigmoidoscopy or colonoscopy is often the first-line investigation and treatment for accessible anastomotic bleeds
Techniques include: thermal coagulation (argon plasma coagulation, bipolar cautery), hemoclips, epinephrine injection (less effective for arterial bleeds)
Endoscopic management is particularly useful for oozing or small vessel bleeding.
Operative Management:
Operative intervention is indicated for severe, refractory bleeding unresponsive to endoscopic therapy, hemodynamic instability despite resuscitation, or if the bleeding source is not amenable to endoscopic control
Options include: re-exploration and direct suture ligation of bleeding vessels, revision of the anastomosis, or diverting stoma creation
Intraoperative endoscopy can help identify the source.
Supportive Care:
Close monitoring of vital signs, urine output, and fluid balance
Continuous assessment of bleeding
Pain management
Nutritional support, typically with parenteral or enteral nutrition initially
Prophylaxis against DVT and stress ulcers.
Complications
Early Complications:
Anastomotic leak, sepsis, ileus, rebleeding, need for blood transfusion, prolonged hospitalization, damage to adjacent organs during intervention, anesthetic complications.
Late Complications:
Anastomotic stricture, incisional hernia, adhesions, prolonged wound healing, psychological impact of severe bleeding and prolonged hospital stay.
Prevention Strategies:
Meticulous surgical technique with careful handling of tissues and optimal suture/staple line construction
Thorough irrigation and hemostasis during surgery
Judicious use of anticoagulants postoperatively and careful reversal if needed
Early recognition and management of coagulopathies
Consideration of patient risk factors for bleeding.
Prognosis
Factors Affecting Prognosis:
Severity of bleeding, hemodynamic stability, promptness of diagnosis and intervention, underlying comorbidities, success of the chosen management modality (endoscopic vs
operative).
Outcomes:
With timely and appropriate management, most anastomotic bleeds can be controlled with good outcomes
However, severe bleeding or delayed intervention can lead to significant morbidity and mortality
Reoperation for bleeding carries higher risks than primary surgery.
Follow Up:
Close postoperative monitoring is essential for at least 72-96 hours for signs of bleeding or leak
Long-term follow-up depends on the underlying condition treated and the complication encountered
Surveillance colonoscopy may be indicated to assess the anastomosis and rule out other pathology.
Key Points
Exam Focus:
Differentiate early vs
late anastomotic bleeding
Understand the indications for endoscopic vs
operative management
Key endoscopic techniques (APC, clips, injection)
Indications for re-exploration
Management of coagulopathy in bleeding patients
Complications of colorectal surgery.
Clinical Pearls:
Always suspect anastomotic bleed in any patient with significant rectal bleeding post-colorectal surgery
Resuscitate first, investigate second
Endoscopy is often the first-line treatment for accessible bleeds
Consider coagulopathy as a reversible cause
Re-operation is reserved for severe, refractory bleeds.
Common Mistakes:
Delaying resuscitation while investigating
Over-reliance on a single diagnostic modality
Inappropriate selection of endoscopic vs
operative management
Underestimating the risk of coagulopathy
Failure to consider alternative causes of rectal bleeding.